Methods Inf Med 2001; 40(04): 288-292
DOI: 10.1055/s-0038-1634171
Original Article
Schattauer GmbH

Determining the Effects of Patient Casemix on Length of Hospital Stay: A Proportional Hazards Frailty Model Approach

A. H. Lee
1   School of Public Health, Curtin University of Technology, Perth, Australia
,
K. K. W. Yau
2   Department of Management Sciences, City University of Hong Kong, Hong Kong
› Author Affiliations
Further Information

Publication History

Received 18 January 2001

Accepted 23 April 2001

Publication Date:
08 February 2018 (online)

Summary

Objectives: To identify factors associated with hospital length of stay (LOS) and to model variations in LOS within Diagnosis Related Groups (DRGs).

Methods: A proportional hazards frailty modelling approach is proposed that accounts for patient transfers and the inherent correlation of patients clustered within hospitals. The investigation is based on patient discharge data extracted for a group of obstetrical DRGs.

Results: Application of the frailty approach has highlighted several significant factors after adjustment for patient casemix and random hospital effects. In particular, patients admitted for childbirth with private medical insurance coverage have higher risk of prolonged hospitalization compared to public patients.

Conclusions: The determination of pertinent factors provides important information to hospital management and clinicians in assessing the risk of prolonged hospitalization. The analysis also enables the comparison of inter-hospital variations across adjacent DRGs.

 
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